The Pap test (a/k/a Pap smear, cervical smear, or Papanicolaou smear) is an important routine gynecological test usually performed annually to screen for early detection of cervical, uterine, and/or vaginal cancer. The Pap test is not intended to be a definitive diagnostic test, but rather a risk assessment-oriented, basic screening procedure. The Pap test is an anatomic pathology assay, where human tissue, cells, and/or secretions from the site of a potential cancer, such as the cervical region, are viewed under a microscope by a trained laboratory professional in search of cellular morphologic changes that evidence, to varying degrees along a standardized continuum of severity (e.g., the Bethesda System), the likely existence and progression of cervical cancer.
A positive Pap test where suspicious cellular changes have been identified is generally followed-up with a colposcopy and/or definitive biopsy. Importantly, given the inherently and otherwise unavoidably imprecise nature of the Pap test, the Pap test owes its legendary efficacy in preventing cervical cancer as much, if not more, to the sheer repetitiveness of the procedure over the course of a woman's life, than to the sensitivity, per se, of any single Pap test. According to cytology experts, the statistical confidence level of an accurate Pap test result rises from a low of 60-70% to upwards of 98% after just three consecutive annual Pap tests.
For this reason, health care standards-setting organizations, such as the American Cancer Society, generally recommend regular (e.g., annual) Pap testing for all women, and for sexually active teens. The American Cancer society recommends that normal women under forty have a Pap smear taken every three years after three consecutive yearly normal Pap smears. However, according to a Gallup poll conducted by the College of American Pathologists (CAP), nearly 40% of those women polled had not had a Pap test within the past year. For many women, the routine screening test would be regularly performed if it could be done in a non-intrusive, private manner. Screening for Cervical Cancer, in Common Screening Tests, David M. Eddy, MD, PhD, Editor, Chapter 10, pages 255-283 (1991).
The Pap test is traditionally taken by a gynecologist by inserting a speculum into the patient's vagina in a manner to expose the cervix of the uterus for sampling tissue, in particular for sampling cells from the endocervical canal and cervical os. To accomplish this, the woman must remain in a reclining position. Various types of speculums and numerous cervical scrapers or probes have been developed for this purpose. The cytologic specimens collected are then placed upon microscope slides for manual or automated reviewing. They are evaluated for hormonal levels and to determine the presence of cancers, precancers and vaginal infections. The test aims to detect potentially pre-cancerous changes (called cervical intraepithelial neoplasia (CIN) or cervical dysplasia), which are very often caused by sexually transmitted human papillomaviruses. The test remains an effective, widely used method for early detection of pre-cancer and cervical cancer. The test may also detect infections and abnormalities in the endocervix and endometrium.
Most of the prior art equipment has been designed for use by gynecologists and is not suitable for use solely by the patient upon herself. There have been previous attempts to develop Pap test apparatus that could be self-administered in order to achieve an economic efficiency by avoiding physician assistance, and improved healthcare through widespread availability. However, there remains a need to provide a more accurate, non-traumatic, self-administered apparatus and method for the collection of cervical tissue samples for cytologic evaluation.